43 Years Of Earth Day: What's Changed Since 1970Now in its 43rd year, Earth Day has become an international day dedicated to promoting environmental awareness and action. Lester Brown, president of the Earth Policy Institute, explains what's changed, as concern about climate change and green energy have come to the forefront of the movement.

Now in its 43rd year, Earth Day has become an international day dedicated to promoting environmental awareness and action. Lester Brown, president of the Earth Policy Institute, explains what's changed, as concern about climate change and green energy have come to the forefront of the movement.

NEAL CONAN, HOST:

On this 43rd Earth Day, organizers declared a theme: the face of climate change, which only suggests how much things have changed since April 22, 1970, when most who turned out for the first Earth Day spoke about clean air and clean water long before climate change had emerged as an issue. Lester Brown joins us now. He's president of the Earth Policy Institute and author most recently of "Full Planet, Empty Plates: The New Geopolitics of Food Scarcity," is on the phone with us from his office here in Washington. Nice to have you back on the program.

LESTER BROWN: Good to be here, Neal.

CONAN: And when you look back at that first Earth Day, well, a whole lot has changed since then, don't you think?

BROWN: Yeah. In 1970, the big focus was on pollution. I mean, it was "Silent Spring" with - in 1962 that had triggered the evolution and formation of the modern environmental movement, and that was pollution-oriented. And, well, we've seen since then is a shift to focus on environmental support systems, like the natural systems, like the forests and grasslands and fisheries and so forth, and what's happening to them. And now, of course, climate change is on the issue, and water has become a major issue.

These were not on the agenda in 1970. At that time, it was largely a focus on pollution, and that was at the time when the Cuyahoga River in Cleveland caught fire because there was so much oil and other combustible material there. So it was pollution. Now, it's many things.

CONAN: It was just a couple of months after that first Earth Day, Congress authorized the creation of the EPA, a federal agency that regulates environmental regulations. The EPA has, of course, become - gone from an agency created with great bipartisan support to one of the most partisan ideas in government.

BROWN: Yeah. I think the - as I recall, the first head might have been Russell Train...

CONAN: I believe you're right.

BROWN: ...who was a Republican, who was one of the early individuals concerned about the - what was happening to the environment. He was an early leader. And so EPA is now 40-plus years old. We - I still think of it as one of the newer agencies around town, but it's not really so new anymore.

CONAN: And we think at the first blush, of course, this issue has been around forever. But going even back to "Silent Spring" in 1962, it is - this kind of consciousness is relatively new, at least as a major public issue.

BROWN: It is, and that's partly because the environmental effects of human activity were quite small. I mean, if you go back to the beginning of the last century, 1900, the global economy then was only, you know, maybe 2 percent of what it is today. So human activity was very limited even if it were in many ways environmentally careless. But now, given the size of the world economy and the pressures on the Earth's natural systems and resources, whether it's forest resources or the capacity of the system to absorb and process waste and, of course, the capacity to absorb CO2 and climate now being probably the big environmental issue.

CONAN: Even 43 years ago, the - climate change was an issue. We just didn't know it yet. Among the things that was occurring that has occurred since then has been an amazing improvement in climate science.

BROWN: There has been - there were very few meteorologists beyond those doing the, you know, the daily weather reports. Climate science was not a big thing because climate had not been changing. I mean, the period since the beginning of agriculture, 11,000 years ago, has been one of rather remarkable climate stability. So the idea of climate change is a relatively recent concept. And then - and the process of human-driven climate change is quite recent historically.

CONAN: And we look at, oh, I guess, probably the biggest example is looking at the past through either tree rings or ice cores to get an idea of what has happened in previous periods of climactic change.

BROWN: Yeah. It's - I mean, we look at these indirect indicators to sort of reconstruct earlier periods in the earth's history or in human history. And what we do know is that for the 11,000 years since agriculture began, things have been sort of stable. But now, suddenly, the farmers now on the land are the first generation of farmers to have to cope with climate change. I mean, we've always had to. When I was farming back in the '50s, we had to worry about weather, you know, and how the weather would affect that particular year's crop. If climate change was not on the - on our minds then, we didn't even know that we were we were going to be changing climate as we now are.

CONAN: Another thing that has changed has been the public attitude. I covered that first Earth Day in New York City. There were rallies all over the country. I was at the one in Union Square in New York. The atmosphere that day was electric. And as mentioned, some of the legislation began to pass shortly thereafter with enormous bipartisan majorities in both houses of Congress and signed by a Republican president. And public opinion polls these days show that the environment is pretty far down the list of people's concerns.

BROWN: That's right. Interestingly, one of the reasons that Richard Nixon was so strong on the environmental issues is because his likely opponent in 1972 was - for his re-election - was going to be Ed Muskie from Maine. And Ed Muskie was a very - had spoken out very strongly on environmental issues and had raised this as a concern.

And in order to sort of undermine that concern, Nixon really took the initiative on the climate front. And then what was, for him, a very much a political issue was, for us, an important advance in public policy as it related to the environment.

CONAN: And as we look ahead, these issues are going to be more and more significant, at least that's what the climate scientists tell us. How did it change to get it - make it more of a priority in people's opinions and in politics?

BROWN: You know, there are various models of social change. One is the - what I call the Pearl Harbor model, where you have an event that changes everything. Sometimes its pressure is gradually building, an awareness building. I call that the Berlin Wall model where things keep building until - in the case of the Berlin Wall, it went down. And sometimes it's difficult to see those tipping points before you reach them. Almost by definition, tipping points are difficult to project and identify.

But my own sense says that we are moving toward a tipping point on the climate issue, and it's going to take a few more droughts like the one in the summer of 2012, an intense heat that greatly reduced the U.S. grain harvest. I think it reduced the corn harvest by close to 30 percent. Or storms unlike anything we've seen before. And then we'll begin to, at some point, realize that climate change is for real. That it's dangerous and it's costly and we need to be doing something about it.

CONAN: Yet, you'd like to think that we could arrive at these kinds of decisions on a rational basis. Don't need a tremendous crisis to focus our attention.

BROWN: One would like to think that, but more often than not, and all too frequently, it takes some sort of a crisis to goad us into action.

CONAN: Well, thanks very much for being with us today.

BROWN: My pleasure.

CONAN: Lester Brown, president of the Earth Policy Institute, author most recently of "Full Planet, Empty Plates: The New Geopolitics of Food Scarcity." He joined us by phone from his office in Washington.

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CONAN: We'd like to take this moment to observe silence scheduled for 2:15 P.M. Eastern Time, which was the moment the explosion started at the end of the Boston Marathon last Monday. This is from the Cathedral of the Holy Cross in Boston. Let's listen.

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CONAN: People around the city of Boston standing, many of them with their heads bowed to mark the moment exactly one week later since the bomb exploded in Boston causing three dead and many, many injured. You're listening to TALK OF THE NATION from NPR News.

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